Obesity is a major public health problem, and about two thirds of the adults in the United States may be overweight, when applying various criteria. The health problems associated with overweight, including type 2 diabetes and cardiovascular diseases to name some, are attributed nearly half a million deaths per year in the USA, and the costs related to overweight may be greater than $100 billion. Treatment of overweight comprises hundreds of diet regimens, and the consumers invest about $30 billion annually on weigh-loss products and services. Lowering daily caloric intake is painful, and the most simple and the least expensive, of course, would be to lower energetic content in the food items in which it is least felt, a good example being a beverage, such as a fruit juice. Even a minor energetic reduction may have a substantial effect when the item in question is consumed in large volumes, the best example being, again, a popular beverage.
Fruit juices have kept their position among the most popular drinks for many years all around the world, 75% of juices consumed in households being orange juices. Oranges, with a yearly production of about 60 million tons, hold a share of nearly one quarter of all fruit produced in the world. For many years, concentrated juice extracts were used, but their sales have declined during last several years due to the increasing popularity of low-carbohydrate and low-caloric diets, and due to the growing demand for what is called healthy and natural products. The orange concentrates may be, for example, five times more concentrated than squeezed juice, making their storage more economical, but health-conscious consumers often prefer not-from-concentrate (NFC) juices, and nondiluted juices. In view of huge and widespread juice consumption, it would be very useful to lower energetic content of the juices, including NFC juices, however small such reduction should be.
Some saccharides, although bearing biochemical energy, cannot be digested in the human alimentary tract, and even though possibly contributing to organoleptic properties of food, they do not contribute to the available energy. Fructose oligomers or polymers, called also fructans, belong among such saccharides; moreover, fructans have been recognized also as prebiotic agents supporting beneficial bacteria such as Bifidobacteria and Lactobacilli. Fructans are produced by various fructosyltransferases in plants, yeasts, fungi and bacteria, and are usually divided to inulines, that comprise predominantly β(2→1) glycosidic bonds, and levans, that comprise predominantly β(2→6) glycosidic bonds between adjacent fructose units. The potential of fructans for human diet was recognized, for example, in U.S. Pat. No. 4,681,771, that describes enzymatic preparation of a low-calorific fructan-based sweetener from sucrose, and its use in producing sweetened low-calorific food products. U.S. Pat. No. 6,808,703 provides microorganisms to be delivered to the intestines, where they should convert digestible saccharides to indigestible ones, thereby treating obesity and diabetes.
It is an object of this invention to provide a process for manufacturing a fruit juice and fruit puree, comprising reducing the content of metabolically available carbohydrates in the juice or puree.
It is another object of this invention to provide a juice or puree having lowered available sugars, but having other components at their natural concentrations.
It is another object of this invention to provide a process for lowering the caloric content of fruit juice or puree, while upgrading the nutritional value of said juice or puree by forming in them prebiotic components.
Other objects and advantages of present invention will appear as description proceeds.